Article 100 and 110.26 panelboard clearance

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Tainted

Tainted

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There needs to be dedicated space clearance above a panelboard per 110.26.

A plumber wants to run a gas line above a circuit breaker enclosure that has two circuit breakers in the enclosure.

Is a circuit breaker enclosure with 2 circuit breakers in it considered a panelboard?

If there was 1 breaker in the enclosure, I wouldn't consider that a panelboard, but what if there's two breakers in the enclosure?
 
See the definition. I would say that whether it has bus would be the point.
 
dkidd said:
See the definition. I would say that whether it has bus would be the point.
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All panels have busses that connects to the breakers.

What's considered a bus though? is a neutral bar considered a bus? are double lugs considered a bus?

What if it has a bus but is not UL 67 listed? Would it still be considered a panel?
 
infinity said:
What does the listing of the equipment say? Panelboards typically have a listing label that tells you what standard they're manufactured to.
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I couldn't get the listing but it looks like this:


1699290899978.png

Would you consider this a panelboard?
 
infinity said:
Yes. The enclosure is a cabinet and the bus/circuit breaker assembly is the panelboard.
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What's considered a bus in this case? what if they have separate dedicated lugs for live and neutral connections? is it still a panelboard?
 
I can't find an exact definition for "bus" or "buses" without it saying "bus bar" or some other additional term, but IMO, that is a panelboard. Do you think you can make an agreement that they are switches? Are the neutrals and equipment ground wires wire nutted individually instead of on a terminal block?
 
If it has a place for the CB's to attach and for the line conductors to attach (see photo) then it has a bus which means that it meets the Article 100 definition of a panelboard.

Panelboard. A single panel or group of panel units designed for assembly in the form of a single panel, including buses and automatic overcurrent devices, and equipped with or without switches for the control of light, heat, or power circuits; designed to be placed in a cabinet or cutout box placed in or against a wall, partition, or other support; and accessible only from the front.
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Grainger_48M370xx1xx887650.JPEG
 
infinity said:
If it has a place for the CB's to attach and for the line conductors to attach (see photo) then it has a bus which means that it meets the Article 100 definition of a panelboard.



Grainger_48M370xx1xx887650.JPEG
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What's the difference between this and a fused disconnect switch? Based on this logic, wouldn't a fused disconnect switch be considered a panelboard?
 
Tainted said:
What's the difference between this and a fused disconnect switch? Based on this logic, wouldn't a fused disconnect switch be considered a panelboard?
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IMO no, look at the definition in post #9. The panelboard is the section in the center, the enclosure is the cabinet which is where the definition states that it gets installed in. Panelboards and disconnect switches are covered under different Articles of the NEC and a different UL listing.
 
infinity said:
IMO no, look at the definition in post #9. The panelboard is the section in the center, the enclosure is the cabinet which is where the definition states that it gets installed in. Panelboards and disconnect switches are covered under different Articles of the NEC and a different UL listing.
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what if you can install only 1 breaker on the enclosure? would that be considered a panelboard?
 
Tainted said:
what if you can install only 1 breaker on the enclosure? would that be considered a panelboard?
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The definition makes no mention of the number of breakers so with everything else being the same why would 1 or 42 circuit breakers make any difference?

Maybe one of the UL gurus can find out of there is any difference in the listing between a single CB and 42 CB Panelboard.
 
infinity said:
The definition makes no mention of the number of breakers so with everything else being the same why would 1 or 42 circuit breakers make any difference?

Maybe one of the UL gurus can find out of there is any difference in the listing between a single CB and 42 CB Panelboard.
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Isn't the whole point of this code is to make sure there is clearance for future circuits above the panel? If there can only be 1 circuit it's overkill for there to be dedicated space.
 
Tainted said:
Isn't the whole point of this code is to make sure there is clearance for future circuits above the panel? If there can only be 1 circuit it's overkill for there to be dedicated space.
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110.26(E), the point of the code clearly states that it is for protection from damage, not future circuits. Is the plumbing contractor giving you a hard time over the location?
 
Rock86 said:
110.26(E), the point of the code clearly states that it is for protection from damage, not future circuits. Is the plumbing contractor giving you a hard time over the location?
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110.26(E) or 110.26(F) says nothing about protection from damage. Nah the plumber is not giving me a hard time, just need to make sure the interpretation of the code is correct before I make the final call..
 
infinity said:
Maybe one of the UL gurus can find out of there is any difference in the listing between a single CB and 42 CB Panelboard.
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Well, the UL guide info for DIVQ has a definition: "Circuit-breaker Enclosure — enclosure only for individual 1-, 2- or 3-pole circuit breaker or for two single-pole breakers not interconnected." And DIVQ doesn't discuss panelboards, just circuit breakers and circuit breaker enclosures. Fairly sure the product pictured in post #9 is listed under DIVQ.

Cheers, Wayne
 
Tainted said:
I couldn't get the listing but it looks like this:


View attachment 2568360

Would you consider this a panelboard?
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Depends... Assuming that the line sides of those breakers are connected to a common source, then yes. The definition of "panelboard" in Article 100 does not say "bus bar", it just says "bus". The term "bus" does not exclusively mean bus BAR, it can include cable. "Bus" is technically short for "omnibus", meaning all together. Any electrical conductor that connects common points of devices all together is a "bus".
 
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